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%I #28 May 02 2017 22:17:18
%S 0,1,4,6,9,10,12,14,8,16,15,22,18,26,21,20,24,34,25,38,28,30,33,46,32,
%T 35,39,27,36,58,40,62,45,44,51,42,48,74,57,52,50,82,49,86,55,54,69,94,
%U 60,56,63,68,65,106,70,66,72,76,87,118,75,122,93,77,64,78
%N a(n) = smallest m for which there is a sequence n = b_1 < b_2 <= b_3 <= ... <= b_t = m such that b_1*b_2*...*b_t is a perfect cube.
%C A cube analog of R. L. Graham's sequence (A006255).
%C Like R. L. Graham's sequence, this is a bijection between the natural numbers and the nonprimes.
%C a(p) = 2p for all primes p.
%H Peter Kagey, <a href="/A277494/b277494.txt">Table of n, a(n) for n = 0..5000</a>
%H Peter Kagey, <a href="/A277494/a277494.txt">Examples of a(n) for n = 0..1000</a>
%e a(0) = 0 via 0 = 0^3
%e a(1) = 1 via 1 = 1^3
%e a(2) = 4 via 2 * 4 = 2^3
%e a(3) = 6 via 3 * 4^2 * 6^2 = 12^3
%e a(4) = 9 via 4 * 6 * 9 = 6^3
%e a(5) = 10 via 5 * 6 * 9 * 10^2 = 30^3
%e a(6) = 12 via 6 * 9^2 * 12 = 18^3
%e a(7) = 14 via 7 * 9^2 * 12^2 * 14^2 = 252^3
%e a(8) = 8 via 8 = 2^3
%e a(9) = 16 via 9 * 12 * 16 = 12^3
%e a(10) = 15 via 10 * 12 * 15^2 = 30^3
%Y Cf. A006255, A277278.
%K nonn
%O 0,3
%A _Peter Kagey_, Oct 17 2016
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